Where can I find the emit() function implementation used in MongoDB's map/reduce? -

Where can I find the emit() function implementation used in MongoDB's map/reduce? -

i'm trying develop deeper understanding of map/reduce in mongodb. figure best way accomplish @ emit's actual implementation. can find it? improve simple implementation of emit(). in mongodb documentation, show way troubleshoot emit() writing own, basic implementation give basic. i'd understand how grouping taking place.

i think definition looking located here:

https://github.com/mongodb/mongo/blob/master/src/mongo/db/commands/mr.cpp#l886

there quite lot of context needed though understand going on. confess, not.

mongodb